Barcelona's Lionel Messi (C) controls the ball against Valencia's Gago during their Spanish first division soccer match against Valencia at Nou Camp stadium in Barcelona September 2, 2012.

Barcelona vs Bayern Munich takes place in the Champions League Semi Final first leg on Tuesday night, in what is being touted as a battle between the two best teams in Europe this year. The game will kick off at 7.45 p.m. ET and can be watched online through free live stream (details below).

Barcelona have been widely recognized in recent years as being the best team in the world, however, during this year's campaign they have stumbled numerous times, and have been beaten by both Celtic and Milan. They managed to progress despite those results and just about scrapped by PSG in the quarter finals on away goals.

Bayern Munich on the other hand have been one of the best teams in Europe for years but have rarely been recognized as "the" best. This year, however, they have been hugely impressive, and have been widely touted as the best team in this year's competition on the form that they've shown.

This first leg will take place in Germany and Bayern will be looking to gain a win to take an advantage with them to the Nou Camp.

Barcelona star player, Lionel Messi, has not played since coming off the substitutes' bench to help his team overcome Paris St-Germain in the last round. However, he will make his comeback from a thigh injury today, and that will be a massive boost for the Spanish giants.

Bayern Munich manager, Jupp Heynckes, has said though that he is not worried about Messi's likely return: "Barca are about more than just Messi. I expect he will be able to play and it is not something which is causing me a headache," Heynckes said.

Messi has already scored 8 times in this season's European competition, and it has been clear Barcelona are missing firepower when he has been absent.

In March he also became the first player in Spanish football history to score against every other team in La Liga consecutively.

Barcelona vs Bayern Munich is scheduled to kick off at 7.45 p.m. ET and can be watched online through free live stream by clicking here.